Key for locks



Dec. 11, 1934.

Patented Dec. 11, 1934 m -mn IDCKS' Lyle n. Shinn, Chicago, in. mumto Chicago j Lock company, Chicago, Ill.

Application septum: '4. 1934. Serial No. 142,52:

, The present invention generally to keys for locks. More particularly] the invention relatest to that .type, of key is designed for use with a lock comprising a cylindrical barrel and a plugfwhich is rotatably mounted in the barrel and is 'adaptedto be locked against rotation relatively to the barrel by means of an annular series of transversely split pin tumblers between it and the barrel. 7

One object of the'invention is to provide a key of the aforementioned type which consists of a hollow, substantiallycylindrical, plug-encircling stem and a flatlm'et'al insert forming a finger gripping member for the" stem, and is so designed that thestem and insert interlock with one another and the unit as a whole may be manufactured at an extremely low cost.

Another object of the invention is to provide a key of the character under consideration in which the inner'end of the hollow, substantially cylindrical stem has, on the outer periphery thereof, an annular series of longitudinally extending, substantially semicylindrical drillings which correspond in number to, and are adapted to receive theouter ends of, the tumblers and form flat surfaced abutments attheir inner ends for engaging the outer end faces of the tumblers and forcing the tumblers inwardly to the proper extent or degree to release the plug for rotation relatively to the barrel when the key is inserted into place in the lock.

Another object of the "invention is to provide a key of the last mentioned character in which the outer end of the hollow, substantially cylindrical stem is closed andembodies a diametric slot for receiving a portion of the grip-forming insert and forming an interlocking connection whereby the stem and insert are secured together.

A further object of the invention is to providea key of the stem and insert type in which the flat metal insert embodies an extension which extends longitudinally of, and fits in a notch in, the inner end of the stem and is shaped to form a rib on the inner periphery of the stem which is adapted to fit in a longitudinally extending groove in the plug of the lock to lock the key and plug against relative rotation when the key is inserted into place in the lock'.

A still further object of the invention is to provide akey of'the hollow stem type which is generally of new and improved construction and is durable as well as easyto manipulate] Other objects of the invention and the various advantagesfand characteristics of the present key construction will be apparent from a consideration of I the following detailed description.'

The invention f consists in the several novel features which are hereinafter described and are more specifically defined by at the conclusion hereof.

In the drawing which accompanies and forms a part of the present specification and disclosure and in which like numerals of reference denote corresponding parts throughout the several viewsz Figure 1 is a perspective of a key embodying key illustrating in detail the manner in which the stem and insert are secured together in interlocking relation;

Figure 5 is a longitudinal sectional view of the Figure 6 is a longitudinal section of thelock, I

taken on the line 6-6 of Figure 4; V

Figure '7 is a transverse section of the lock; Figure 8 is a perspective of the hollow, substantially cylindrical stem of the'key, showing in detail the manner in which the abutment-forming, tumbler-receiving drillings are formed and arranged on the outer periphery of the inner end of the stem; and

Figure!) is a perspective of the insert of the key. The key which forms the subject matter of the invention consists of a stem 10 and a flat metal insert 11 and is designed for use with a barrel type lock 12. This lock is adapted for general use or application and, as shown in the drawing, comprises a cylindrical barrel 13, a plug 14 and an annular series of transversely split pin tumblers 15. The barrel 13 is hollow and embodies at the front end thereof an inwardly extending annular flange 16 which is formed as an integral part of the barrel and defines an annular shoulder 17. The plug 14 is disposed in the barrel and is supported by means of a bushing 18 so that it is rotatable relatively to the barrel. The front end of the plug is flush with the front end of the barin diameter to, and fits rotatably against, the inner periphery of the barrel 13. The rear endof the bushing 18 is provided with a plate 22-which is disposed adjacent to the rear end of the barrel and embodies a radially extending lug- 23. The

inner end of the barrel to limit the rotation of the plug with respect to the barrel. The tumf latter is adapted to co-act with a lug 24 on the blers 15 are slidably mounted in holes 25 in the enlarged part21 of -the bushing 18 and in holes 26 in an outer bushing 27. This outer bushing surrounds the rear end of the bushing 18 and is fixed, by way of a pin 28, to the rear end of the barrel 13. Compression springs 29 are disposed in the rear ends of the holes 26 and serve to force the tumblers 15 toward and into engagement with the shoulder 17 at the front of the barrel. The tumblers are transversely split at different distances from the front ends thereof and are adapted, when forced inwardly by the key as hereinafter described, to have the splits thereof brought into registry with the meeting faces of the outer bushing 27 and the enlarged part 21 of the bushing 18, so as to free the plug for rotation relatively to the barrel. when the key is removed the springs 29 force the tumblers outwardly so that the split portions thereof are out of registry with the meeting faces of the outer bushing and the enlarged part 21 of the bushing 18 and the plug is thus locked against rotation relatively to the barrel. A stud 30 is formed on the plate 22 and serves as an instrumentality for throwing a bolt or like locking element in response to rotation of the plug relatively to the barrel. The rear end of the barrel and the outer bushing 27 have registering holes 31 and 32, respectively, for receiving a pin (not shown) for securing the barrel of the lock in place. The front end of the plug 14 has a longitudinal groove 33 which extends from the front face thereof to the front face of the enlarged part 21 of the bushing 18. The tumblers 15 are so arranged in the holes 25 and 26 that the inner portions of the outer ends thereof are spaced outwardly from the plug 14 and are in alignment or registry with the annular passageway 19 between the plug and the flange 17 (see Figure 4).

The stem 10 of the key is hollow and is adapted to fit around the outer end of the plug 14 of the lock and to pass through the annular passageway 19. It is formed of substantially cylindrical, metal stock, and is preferably made on a screw machine or other type of automatic metal shaping apparatus. The inner end of the stem is drilled or reamed to form a bore 34. This bore is the same in diameter as the front or outer end of the plug 14 and receives the plug when the key is inserted into the look. When the key is in place in the lock the inner end of the stem fits against the front face of the enlarged part 21 of the bushing 18. In addition to the bore 34 the inner end of the stem 10 has an annular series of substantially semicylindrical drillings 35. These drillings are formed in the outer periphery of the stem and correspond in number to the tumblers 15 of the lock. They are spaced equidistantly apart and form fiat surfaced, tumbler-engaging abutments 36 at their ends. When the stem 10 is passed through the passageway 19 the drillings 35 are adapted to receive the portions of the tumblers which are aligned with the passageway and the abutments 36 engage the front faces of the tumblers. The drillings 35 are of such depth that when the stem of the key is in place against the front face of the enlarged part 21 of the bushing 18, the abutments 36 hold the tumblers so that the split portions thereof register with the meeting faces of the enlarged part 21 and the outer bushing 27. By reason of the fact that the tumbler-engaging abutments are formed by drillings in the outer periphery of the stem, the inner periphery of the stem is smooth or unbroken at the inner or front end of the stem with th? t l l that the key will slide readily around the plug of the lock when inserted into the passageway 19. An additional feature or advantage of having the drillings 35 in the outer periphery of the stem is that the wall of the stem may be made extremely thin without likelihood of damage to its inner or front end and hence the passageway 19 in the lock may be made of such thinness as to make picking of the lock or unauthorized tampering with the tumblers extremely dimcult. The inner end of the stem, that is, the end with the drillings 35, has a notch 37. This notch extends longitudinally of the stem and terminates inwardly of the extreme inner end of the stem. The other end of the stem, as shown in Figure, 6, is closed and embodies a diametric slot 38. This slot is disposed ,in the same plane as the notch 37.

The insert 11 is preferably in the form of a stamping and embodies a finger-gripping member 39, a cross-piece 40, and an extension 41. The finger-gripping member 39 is elongated transversely with respect to the stem'so that the key may be readily turned in connection with looking or unlocking of the lock. The cross-piece 40 fits within the slot 38 and forms an interlocking connection between the insert and the stem, whereby the two are secured together against relative rotation. The insert is preferably fixed to the stem by pinching or soldering the slotted portions of the closed end of the stem around the cross-piece 40. The extension 41 extends alon one side of the stem 10 and has a part 42 which extends through the notch 37 and forms a longitudinal rib 43 along the bore 34. This rib is adapted to fit within the groove 33 in the front end of the plug 14 when the key is inserted into place and serves to lock the stem and plug together so that the plug may be rotated by the key when it is desired to unlock the lock. The rib-forming part 42 of the extension 41 of the insert has a central cut-out 44 on the outer side thereof to accommodate the annular flange 16 when the key is inserted in place in the lock. This cut-out extends to a point slightly inwardly of the outer periphery of the stem 10 and permits the key to turn relatively to the barrel of the lock. The extreme outer end of the rib 43 underlies the portion of the stem at the inner end of the notch 37, as shown in Figure 6 of the drawings. Because of this, the rib-forming part of the extension 41 of the insert is held against outward displacement with respect to the stem. The outer end of the rib-forming part 42 of the extension is shaped to form a ward 45. This ward is located outwardly of the cut-out 44 and extends outwardly and radially with respect to the stem 10 of the key. It is designed to pass through a groove 16 in the flange 16 of the barrel of the lock when the key is inserted into the lock. When the key is turned relatively to the lock barrel 13, the ward 45 rotates within the portion of the barrel which is inwardly of the annular shoulder 17. The groove 16 is so located with respect to the stud 30 that the key may be inserted into the lock and removed from the lock only when the plug is in its locked position. When the lock is to be unlocked the ward 45 is aligned with the groove 16 and the key is shifted forwardly so as to pass the stem around the plug and slide the rib 43 through the groove 33 in the front end of the plug. During forward shift of the stem of the key, the abutments 36 at the closed ends of the drillings 35 engage the tumblers 15 and force the tumblers inwardly until the split portions thereof register with the meeting faces of the outer bushing 2'1 and the enlarged part 21 of the bushing 18. As soon as the extreme inner end of the stem of the key strikes against the outer face of the enlarged part 21 of the bushing 18 and the ward 45 is clear of the groove 16, the key may be turned so as to rotate the plug 14 relatively of the barrel and shift the lock into its unlocked position. In order to lock the lock, it is only necessary to rotate the key until the ward 45 is in line with the groove 16 and then remove the key from the lock. The ward 45 is preferably extended longitudinally of the stem of the key so that it overlies the part of the stem at the inner end of the notch 37, and forms with the inner end of the rib 43 a fork formation at the end of the extension 41, whereby the extension is locked against transverse displacement with respect to the stem.

In assembling the key the rib-forming part 42 of the extension 41 is inserted through the notch 37 in the stem and the inner ends of the rib and ward are placed in straddled relation with the portion of the stem at the inner end of the notch 3'7. Thereafter the cross-piece 40 of the insert is shifted into its proper position in the slot '38 and is fixed to the .closed end of the stem, as hereinbefore described.

The herein described key is extremely durable because of the specific construction thereof and may be manufactured at a low cost due to the fact that it consists of but two parts. By virtue of the fact that the tumbler-engaging abutments 36 are formed by substantially semicylindrical drillings in the outer periphery of the inner end of the stem of the key, the inner end of the stem is fiat or unbroken and hence may be readily aligned with, and inserted into, the annular passageway 19 between the flange 16 and the plug 14 of the lock.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I regard as new and desire to secure by Letters Patent is:

1. As a new article of manufacture, a key for a lock having a barrel and a cylindrically shaped plug rotatably mounted in the barrel and adapted to be locked in place by an annular series of pin tumblers between it and the barrel, said key comprising a cylindrically shaped stem having a central longitudinally extending bore for receiving slidably the outer end of the plug and also having around the bore a comparatively thin annular wall portion with its inner edge and periphery smooth and unbroken and with subf stantlally semicylindrical, tumbler-receiving drillings in its outer periphery leading to its inner edge and forming fiat surfaced abutments for operating the tumblers when the stem is slid onto the plug, and a finger-piece at the outer end of the stem.

2. As a new article of manufacture, a key for a lock having a barrel and a plug rotatably mounted in the barrel and adapted to be locked in place by an annular series of pin tumblers between it and the barrel, said key comprising a substantially cylindrical stem having at one end thereof a central-plug-receiving bore and tumbler-operating abutments around the bore, as well as a longitudinal notch leading to said bore, and a flat metal insert attached to the other end of the stem and embodying a finger-piece whereby the key may be turned for lock-operating purposes and an extension extending along the side of the stem and having a part passing through the notch and forming within the bore an internal longitudinal rib for disposition in a longitudinal plug-tuminggroove in the plug of the'lock.

3. As a new article of manufacture, a key for a lock having a barrel and a longitudinally grooved plug rotatably mounted in the barrel and adapted to be locked in place by an annular series of pin tumblers between it and the barrel, said key comprising a substantially cylindrical stem having at one end thereof a central plug-receiving bore and tumbler-operating abutments around the bore as well as a longitudinal notch leading to said bore and also having its other end closed and provided with a diametric slot in the same plane as the notch, and a flat metal insert fitting and secured in the slot and embodying a fingerpiece whereby the key may be turned for lockoperating purposes and an extension along the side of the stem and having a part passing through the notch and forming within the bore an internal longitudinal rib for disposition in the groove of the plug.

4. As a new article of manufacture, a key for a lock having a barrel with a ward-receiving groove at one end and a plug rotatably mounted in the barrel and adapted to be locked in place by an annular series of pin tumblers between it and the barrel, said key comprising a substantially cylindrical stem having at one end thereof a central plug-receiving bore and tumbleroperating abutments around the bore, and a flat metal insert attached to the other end of the stem and embodying a finger-piece whereby the key may be turned for lock-operating purposes and an extension extending along the side of the stem and provided at the end thereof with a ward adapted to pass through the ward-receiving groove of the barrel when the key is inserted into place with respect to the lock.

5. As a new article of manufacture, a key for a lock having a barrel with a ward receiving groove at one end and a plug rotatably mounted in the barrel and adapted to be locked in place by an annular series of pin tumblers between it and the barrel, said key comprising a substantially cylindrical stem having at one end thereof a central plug receiving bore and tumbler operating abutments around the bore as well as a longitudinal notch leading to said bore, and a fiat metal insert attached to the other end of the stem and embodying a finger-piece whereby the key may be turned for lock operating purposes, and an extension extending along the side of the stem and having a part passing through the notch and forming within the bore an internal longitudinal rib for disposition in a longitudinal plug turning groove in the plug of the lock, and also having at its outer end a ward adjacent the outer periphery of the stem adapted to pass through the ward receiving groove of the barrel when the key is inserted into place with respect to the lock.

LYLE B. SHINN. 

